Spark-plug guard.



PATENTED SEPT. 1, 1908.

R. S. KEARNEY. SPARK PLUG GUARD.

APPLICATION TILED APB. 9,1001.

ROBERT S. KEARNEY, 01 NEW YORK, N. Y.

SPARK-PLUG GUARD.

Specification of Letters Patent.

Patented Sept. 1, 1908.

Application filed April 9, 1907. Serial No. 367,146.

b all whom it may concern:

Be. it known that. I, ROBERT S. KEARNEY, citizen of the United States, residing at New York, in the county of New York and State of New York, have invented certain new and useful linprovements in Spark-Plug Guards, of .which the following is a specification.

This invent ion relates to protecting means for inclosing an otherwise exposed spark ring for the purpose of minimizing its frangi- )llli), overcoming the tendency of theeleetric current to short circuit and. the. plug to crack upon contact with spray, rain or moisture of any description, and furnish a complete protection from blows of tools used about an engine, oars, poles and other paraphernalia in use about a boat or vehicle equipped with an explosive engine.

A furtherpurpose of the invention is to provide a guard which may remain attached. to the. plug to protect the same when disconnected from the engine and when in position will add to the appearance of theengine rather than detract from the looks thereof.

For a full description of the invention and the merits thereof and also to acquire a knowledge of the details of construction and the means for effecting the result, reference is to be had to the following description and accompanying drawings.

While the invention may be adapted to different forms and conditions by changes in the structure and minor details without departing from the spirit or essential features thereof, still the preferred embodiment is shown in the accompanying drawings, in which:

Figure l is a side elevation of a s ark plug having the improved guard applie thereto. Fig. 2 is a sectional view thereof. Fig. 3 is a detail ers ective view of an end portion of the i101. yo the guard. Fig. 4 is a detail perspective "icw of the cap inverted.

(oi-responding and like parts are referred to in the following description and indicated in all the views of the. drawings by the same reference characters.

The spark plug 1 may be of any pattern or make and is provided with a coupling 2 by means of which it is connected to the engine. In accordance with this invention the coupling 2 is provided upon its outer side with a threaded portion 3 exterior to the flange 4 to which the staple, wrench or like tool isfitted when screwing the coupling home or unscrewing the same from the engine or like part to which the spark ring is fitted.

The guard comprises t. ie body .3 and cap 6. The body 5 is hollow and consists of n cylindrieal shell or easing the. lower end being internally threaded to makea screw thread connection with the part. I; of the coupling 2. The en) t) is of rounded form and is hinged to the )ody at. 7 and when closed is secured by means of a. catch 8. The hinge 7 is of such construction as to be. liltl-( tltzt-ll)" invisible and not to otter any projection which would detract from the aprmarmwe of the guard and he in the way. The hinge is formed of a projection t) of the cap adapted to [it into a notch 10 in the upper edge of the body, a pin passing through the oven-lapped parts to pivotnll connect. them. The catch 8 is an integral part of the cap and projr-wts therefrom and is adapted to enter a depression 1] in a side of the body 5 near the upper end thereof. The projection 8 and depression 1] are such as to admit of the catch coining about flush with the outer surface of the guard. The catch is located by preference diametrically o posite to the hinge joint. A notch 12 is ormed in the upper edge of the body 5 to receive the conductor 13 by means of which the current is conveycd to the spark plug. To prevent rain, s may or other foreign matter from entering the notch 12 a projection or hood 14 extends from the cap 6 and forms a protector to cover the said notch. The pendent hook 14 curves outward and downward and is of such rela-'' tive proportions as to conform to the shape and contour of the conductor 13 and form a covering which will shed moisture or any other matter tending to enter the notch 1.2.

The plug may be detached from the engine without necessitating the removal of the guard, hence is protected at all times from injury. It is also apparent that the guard may be removed at any time for any purpose or that access may be had to the plug without necessitating the removal of the guard the cap being released and drawn up out of the way upon its hinge or pivotal connection with the body 5. By forming the guard of metal such as brass or copper it may be polished and will add to the appearance of the engine, while at the same time protect the spark plug from injury either from knocks or from moisture coming in contact therewith.

Having thus doscribod the invention, what is claimed as new is:

l. A guard for spark plugs comprising a cylindrical shell open at both ends and adapted to slip over the spark plug and inclose the smno, one end of the shvll lining, sv-

cured t0 the base of tho spark plug, whilo tho opposite and is provided with :1 non-11,21 r0- lnovahle; cap 1.].01lll21-lly closing the not-(110d end of the shell, and a hood cu lriod hy the cap and projecting over the said notch.

2. A guardfor spark plugs comprising a cylindrical shell open at both ends and mluptod to slip over the spark plug and in- \vitnossvsz lonx (.2. AUAR, LOI'IS M. FULTON. 

